Brillouin-Based PON Monitoring With Efficient Compensation of Gain Profile Variation Using Frequency-Swept Pump Pulse

We propose and demonstrate a novel scheme for the Brillouin-based loss monitoring of branch sections in passive optical networks. The proposed scheme with a linearly frequency-swept pump pulse can compensate for the variation in the Brillouin gain profile along fiber links with a higher pump energy efficiency than a conventional frequency shift averaging scheme. In principle, we clarified the Brillouin acoustic wave dynamics with a frequency-swept pump pulse, and designed the performance of a Brillouin-based loss monitoring technique. Experiments with 1.65 μm directly modulated distributed feedback lasers were successfully demonstrated, which revealed satisfactory performance for practical use in the remote monitoring of field deployed PONs.